基于平衡技术的微带低通滤波器版图优化设计

微带线结构的不连续性,使反射损耗和插入损耗较大,影响滤波器性能。利用平衡法提升滤波器并联分支中较低的特性阻抗,达到降低微带线宽度的目的,从而均衡整个滤波器的宽度,使版图仿真优化。以一个5阶切比雪夫微带低通滤波器设计为例,仿真结果表明,滤波器通带内反射损耗从-9.566dB降低到-15.837dB,插入损耗从0.679dB降低到0.322dB,与直接采用Richards变换和Kuroda规则设计微带低通滤波器相比,该方法能缩短滤波器设计周期,获得满意的滤波器性能。

Design of microstrip low-pass filter layout optimization based on balanc technology

The discontinuity of the microstrip line structure makes reflection loss and insertion loss bigger,and affects the filter performance.In this paper,balancing method is used to enhance the lower characteristic impedance of the parallel filter branch to achieve the purpose of reducing the width of microstrip line,accordingly to balance the width of the filter and to optimize the simulation layout.Taking the design of a fiveth-order Chebyshev microstrip low-pass filter as an example,its simulation results show that the internal reflection loss of the filter passband decreases from-9.566 dB to-15.837 dB and the insertion loss cuts down to 0.322 dB from 0.679 dB.Compared with directly adoptting Richards transform and microstrip low-pass filter designed by Kuroda rule,this method can shorten the design cycle of filter and make the filter performance satisfactory.